1. Field of the Invention
The invention relates to a chain lock for high-strength steel chains, the lock having two lock parts that are the same and can be joined together in a rotation-symmetry arrangement with one another, in the longitudinal direction. There is a longitudinal stay having arc segments that follow it at both ends. One of two coupling elements that are configured complementary to one another is assigned to the two arc segments of each lock part. One of these elements is configured as a locking stay that follows the longitudinal extension of the lock part, and the other element is configured as a stay accommodation. The locking stay of the one lock part that engages in the stay accommodation of the other lock part rests against the complementary coupling surface of the stay accommodation with its coupling surface formed by the face end in the joining direction.
2. The Prior Art
High-strength steel chains are used, among other things, in underground mining, for example as chain scraper conveyors. Such steel chains consist of individual chain links that are linked into one another and welded. To open and close such a steel chain, it has a chain lock. Such a chain lock, which is known as a block lock, is described in German Patent No. DE 298 11 332 U1. A locking stay and a stay accommodation serve as the coupling elements for connecting the two lock parts for forming the chain lock. The locking stay and, accordingly, the stay accommodation, have a coupling surface that is curved at a uniform radius and therefore sickle-shaped, pointing in the joining direction of the two lock parts, in each instance. When tensile stress is applied by the chain links that are hooked into such a chain lock, the coupling elements of the two lock parts that interact with one another automatically lock together. To absorb transverse forces, the coupling surfaces of the locking stays additionally have a projection that forms an undercut, the coupling surface of which is also rounded with a uniform radius. The stay accommodation of the other lock part, which is configured complementary to the locking stay, in order to accommodate it, has a correspondingly dimensioned pocket to accommodate the projection. The essential factor for the ability of the chain lock to withstand stress, in accordance with its intended purpose, is that the coupling surfaces of the locking stays rest against the complementary coupling surfaces of the locking stays of the other lock part, in each instance. Locking pins that are disposed in complementary bores of the joined lock parts, in the region of the arc segments, fix the two lock parts that have been joined together in place, in the longitudinal, i.e. joining direction.
Block locks of the aforementioned type have proven themselves in practice, because of their strength and also because of their great resistance to tensile stress. Nevertheless, it would be desirable if the durability of such a chain lock could be improved, in order to increase the useful lifetime, without having to configure the chain lock, i.e. its longitudinal stays and its arc segments, with greater material thickness for this purpose.